A capacitive touch screen is a human-machine interaction apparatus that mainly consists of a driving electrode and a sensing electrode. A touch control chip may drive signals with different frequencies to the driving electrode by configuration, and the sensing electrode is responsible for receiving signals. An operation, such as digital signal processing, is performed on the signals received by the sensing electrode, to obtain raw value data. The touch control chip can determine a position of a touch point on the capacitive touch screen according to the raw value data.
The capacitive touch screen is often affected by a common mode noise during use, such as a noise of a charger. In a case of a common mode interference noise, if the raw value data is mixed with noise data, it would result in abnormal mutual capacitance data, which will result in a point appearing phenomenon or a point disappearing phenomenon when it reacts to data for determining a touch position, thereby affecting detection accuracy of the touch position.